This invention relates to a cobalt oxide catalyst particularly suitable for the oxidation of ammonia to nitric oxide and to a process for producing said catalyst.
Although it has long been known that cobalt oxide is effective in ammonia oxidation, industrial processes for the manufacture of nitrogen oxides have generally used a platinum-based catalyst such as platinum-rhodium, usually in the form of metal gauze. This is expensive in initial cost and also in operating cost because metal is lost from the catalyst and is not recovered completely from the reaction gases.
One problem in the use of cobalt oxide catalyst is to ensure high activity coupled with adequate resistance to disintegration of the catalyst particles at the high temperature of the oxidation, particularly when the catalyst bed is raked to shift the catalyst particles to present fresh surfaces. We have now discovered a method of making a highly active, particulate cobalt oxide catalyst which has a much lower incidence of disintegration during ammonia oxidation. Moreover, with use of the preferred catalyst derived from electrolytic grade cobalt, a conversion efficiency of ammonia to nitric oxide of up to 99.4 percent has been obtained.